Guitars are stringed musical instruments used by amateur and professional musicians. Guitars include acoustic guitars which generally include a hollow body connected to a neck. The body includes a soundboard and backboard, with the soundboard typically including a centrally-located sound hole. The body further includes a bridge and tailpiece located near the end of the guitar opposite the neck which serve to anchor one end of the strings.
Guitars also include electric guitars which typically include a solid body connected to a neck. The body of an electric guitar includes pickups that generate or modulate an electrical signal in response to vibration of the strings and includes controls that select or modify the electrical signals. The body also includes a bridge and tailpiece to anchor one end of the strings.
The body of an acoustic guitar or electric guitar is connected to the neck of the guitar using a headblock. The neck includes a headstock at the end of the neck opposite the body. The headstock includes tuning keys or machine heads used to adjust and maintain the tension of the strings. The neck also includes the nut, a small strip of medium-hard material that supports the strings at the periphery of the headstock. In some instruments, the neck includes a truss rod disposed along the long axis of the neck and used to generate tension to counteract the tension placed on the neck by the strings. Typically the tension of the truss rod can be adjusted.
The neck also includes a fretboard or fingerboard disposed between the body and the nut. The fretboard spans the entire width of the neck and is mounted above a flat surface of the neck oriented towards the strings. The fretboard provides a surface upon which a person playing the instrument presses down the strings to adjust the effective length of the strings. Many other types of stringed musical instruments include a fretboard mounted to a neck including violas, violins, cellos, upright basses, ukuleles, fiddles, lutes, banjos, mandolins, dulcimers, and shamisens. On many instruments, the fretboard includes frets which permit the instrument to play a discrete scale of notes as determined by the spacing of the frets and the composition and tension of the strings. Alternatively, some instruments have a fretboard that does not have frets. Some instruments have a fretboard that includes decorative markings or markings to indicate the location where strings should be pressed to create particular notes. The markings on a fretboard can be inlays in the fretboard.
The fretboard must remain close to but not contact the unpressed strings along the entire length of the fretboard. The fretboard must not create any buzz, rattle, distortion or other undesirable vibrations. In addition, many players desire a particular tactile sensation when touching the fretboard. Finally, a fretboard has a substantial effect on the appearance of the instrument and are often designed to enhance the aesthetics of the instrument. Accordingly, some materials are highly desired as fretboard components, including exotic and difficult to obtain woods and expensive natural and synthetic materials.
Some materials that are desirable for a fretboard change dimension in response to changes in environmental factors such as temperature, humidity, pressure, or the moisture content of the material. Some materials change dimensions in response to surface treatments such as oiling or varnishing, for example, as when wood grain rises after application of a polyurethane finish. The changes in the dimensions can differ for different materials subjected to the same environmental changes or surface treatments. Using different materials together can therefore be difficult, in particular when a precise fit is desired or when the pieces being fitted together are relatively large or relatively thin.